64 basically go haywire," a Pentagon ex- pert who has studied this subject told me. "The communications satellites drift off to Pluto." Certain intelli- gence-gathering satellites in low earth orbit would be in especially bad shape, he said, because the Sunnyvale facility has to "feed" them with instructions every time they complete an orbit. "You should see them scrambling when one of these satellites comes within range." Desmond Ball esti- mated that the typical United States defense satellite might be able to re- main In operation for three or four days; the most critical satellites- among them DSP East-which re- quire a great deal of caretaking atten- tion from the ground, could go out of service within hours. In some cases, a high level of redundancy is built into the strategic-command system, with a large number of backup facilities and alternative means of carrying out criti- cal tasks. In other cases, the system is dangerously thin. Sunnyvale is an ob- vious example. Another Air Force sat- ellite-control facility is under con- struction in Colorado, but experts do not believe that presenting two tar- gets to the Soviets instead of one will greatly complicate their ability to dis- rupt the operation of United States de- fense satellites. ACCORDING to what I saw at n.. NORAD on October 24, 1983, DSP East was functioning normally that day. (In the Missile Warning Center, officials refused to discuss the status of the satellite; in the Command Post, however, I observed a green light indicating that DSP East was in service.) Provided that it had not been jammed or otherwise incapacitat- ed, this sensor would have been able to gather data about the launching of Soviet ICBMs at the time I have designated H Hour. This informa- tion would then have to be transmit- ted to NORAD-which is something DSP East can't do directly. Cheyenne Mountain is on the other side of the globe, and an extended set of commu- nications links must be used to retrieve the satellite's warning signals. A key part of the communications relay between NORAD and its principal early-warning satellite is a ground sta- tion in Australia that functions as the "downlink" for the satellite. It re- ceives raw data from DSP East, processes the information immediately, using dual I.B.M. 360-75J computers, and relays the results back to NORAD. The station, which has been the focus of considerable political controversy in Australia, occupies eight acres of land at Nurrungar, about three hundred miles northwest of Adelaide, and for many years it has been the only "read- out station" for our most important early-warning satellite. The station has various means-radio, satellite, and undersea cable-of getting urgent data back to the United States. Depen- dence on a single downlink for DSP East, like the reliance on the unique installation at Sunnyvale, has been a major cause for concern-especially since the Australian station includes a highly exposed set of antennas and transmitters, which present extremely "soft" targets to any enemy. The sta- tion could be directly attacked by a Soviet ICBM or submarine-launched missile. It could also be disabled by less dramatic methods. Its satellite anten- nas (there are two of them, forty feet high and housed inside plastic domes) or its power supplies or its communi- cations lines could be rendered inoper- able by what the military refers to as "sappers" -a smal1 team of techni- cally adept saboteurs armed only with conventional weapons and explosives. "Since relatively few fixed installa- tions are involved, sabotage must . . . be considered a significant threat in a sudden nuclear attack," a special re- port to Congress concluded in 1981. "A coördinated series of sabotage inci- dents could be particularly disruptive in such a time-sensitive scenario as a nuclear attack. Obviously, poorly exe- cuted sabotage efforts could serve to increase warning time. Nonetheless, if acts of sabotage confounded clear eval- uation for only a few tens of minutes, command-post aircraft, bombers, and tanker aircraft might be destroyed on the ground." "It is inconceivable to me that if the Russians were going to start a war they'd not start by knocking out the early-warning sites," one of the Pen- tagon's leading experts on command- system design told me. The danger of attacks against the sensor sites was also emphasized by the major Penta- gon connectivity studies, which noted the particularly acute vulnerability of NORAD's Australian link. It turned out that it would not even be neces- sary to attack the N urrungar ground station itself, since subtler means could break its connection back to Chey- enne Mountain. For instance, govern- ment investigators discovered, to their amazement, that with no trouble whatever saboteurs could simply cut the undersea cable from Australia at the point where it came ashore in an unprotected A.T. & T. building in San Francisco. "A lot of things were overlooked as we built those systems," General Richard Ellis, former commander-in- chief of the Strategic Air Command, has conceded. "Anyone could just walk in the door to a switching center that had the name of the originating terminal on a sign. In other words, it identified the overseas station, and you knew right away that this was the United States terminal for that infor- mation, and was highly vulnerable to anything anybody wanted to do to it." And General Robert Marsh, until re- cently the head of the Air Force Sys- tems Command, acknowledged, "We have highly visible, highly vulnerable switching nodes throughout our oom- munications environment. We put up big signs on our coastline-'Subma- rine Cable, Do Not Dredge Here,' and so on-and some of those [cables] are our only lifeline to important sensor stations." Instead of-or in addition to-severing the main cable connec- tion in Northern California, saboteurs could as easily try to cut it at its Australian end, in Sydney, or at some point in between, such as Wellington, New Zealand, or Hawaii. I was informed at NORAD that the "situation" concerning the A. T. & T. building in San Francisco had been "corrected." I was not told how. One government expert said that about all you could do was put in "rudimentary security arrangements"-some fences, guards, and locked doors-and take down the sign identifying the cable, but these improvements would afford little protection against skilled attackers. Another step that NORAD has taken to reduce the vulnerability of its Aus- tralian connection is, if anything, even less effective. The information packet . it provided me with included a map showing the "support organizations" connected to NORAD. The name of the Australian ground station was covered